This invention relates to a light-sensitive copying material containing an ooquinone diazide compound as a light-sensitive component.
It is known that o-quinone diazide compounds decompose at the diazo group upon radiation with actinic rays to become carboxyl group-bearing compounds. When a copying layer containing an o-quinone diazide compound is imagewise exposed and then treated with an alkaline developer, therefore, the exposed area is removed and the non-exposed area remains as an image. Accordingly, an o-quinone diazide compound has become noted as a light-sensitive component of the so-called positive type. These compositions comprise generally not only an o-quinone diazide compound but also an alkali-soluble resin such as a phenol-formaldehyde resin to reinforce the image strength and to increase the film-forming properties, and can preferably be used in the form of a uniform composition, in addition, with additives such as dyes and plasticizers.
Unfortunately, these resins and additives tend to compete with the diazide for the ultraviolet exposure radiation and absorb substantial quantities of such radiation. The net effect is a composition having overall reduced light sensitivity.